These tables are only used by encoders and only for the current picture;
ergo they need not be put into the picture at all, but rather into
the encoder's context. They also don't need to be refcounted,
because there is only one owner.
In contrast to this, the earlier code refcounts them which
incurs unnecessary overhead. These references are not unreferenced
in ff_mpeg_unref_picture() (they are kept in order to have something
like a buffer pool), so that several buffers are kept at the same
time, although only one is needed, thereby wasting memory.
The code also propagates references to other pictures not part of
the pictures array (namely the copy of the current/next/last picture
in the MpegEncContext which get references of their own). These
references are not unreferenced in ff_mpeg_unref_picture() (the
buffers are probably kept in order to have something like a pool),
yet if the current picture is a B-frame, it gets unreferenced
at the end of ff_mpv_encode_picture() and its slot in the picture
array will therefore be reused the next time; but the copy of the
current picture also still has its references and therefore
these buffers will be made duplicated in order to make them writable
in the next call to ff_mpv_encode_picture(). This is of course
unnecessary.
Finally, ff_find_unused_picture() is supposed to just return
any unused picture and the code is supposed to work with it;
yet for the vsynth*-mpeg4-adap tests the result depends upon
the content of these buffers; given that this patchset
changes the content of these buffers (the initial content is now
the state of these buffers after encoding the last frame;
before this patch the buffers used came from the last picture
that occupied the same slot in the picture array) their ref-files
needed to be changed. This points to a bug somewhere (if one removes
the initialization, one gets uninitialized reads in
adaptive_quantization in ratecontrol.c).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It is currently a "Picture", an mpegvideo-specific type
that has a lot of baggage, all of which is unnecessary
for new_picture, because only its embedded AVFrame
is ever used. So just use an ordinary AVFrame.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Modifying static storage must not happen because of multithreading
(except initialization of course), so add const to the pointed-to type
for pointers that point to static storage.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
This option allows more control over the use of intra macroblocks in
predictive frames.
By using '-intra_penalty max', intra macroblocks are never used in
predictive frames.
It is useful for glitch artists to generate input material. This option
allows them to split and merge two video files while maintaining fluid
motion from the second video without having intra macroblocks restoring
chunks of the first video.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This option is extremely codec specific and only a few codecs employ it.
Move it to codec private options instead: mpegenc family supports only 3
values, xavs and x264 use 5, and xvid has a different metric entirely.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
The most interesting parts are initialization in ff_MPV_common_init() and
uninitialization in ff_MPV_common_end().
ff_mpeg_unref_picture and ff_thread_release_buffer have additional NULL
checks for Picture.f, because these functions can be called on
uninitialized or partially initialized Pictures.
NULL pointer checks are added to ff_thread_release_buffer() stub function.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
This misfeature is most likely completely useless and conflicts with
removing the mpegvideo-specific fields from AVFrame. In the improbable
case it is actually useful, it should be reimplemented in a better way.